Punches need to be worn out and should not crack or chip. Punch chipping and cracking can be caused by a variety of factors. Here is a simple check list that will help minimize the chances of this happening.
Lock coupling nut loose
This allows the punch to "move" when it is being punched. This movement can cause uneven pressures.
Missalignment
If the die is not aligned with the hole in the die, an uneven clearance can result. The result will be uneven pressure on the face of the die.
Unsufficient clearance between the die and punch
The standard clearance for punch tooling that is less than 1/2" thick is 1/32" total clearance. The material to be punched that is 1/2" or thicker will require one-quarter of an inch clearance". For mild steel over 3/4" thick may require even more die clearance.
Uneven stripping
This happens because the stripper in the machine does not firmly and evenly ensure that the plate is held down during the "up" stroke. This occurs when the entire plate's weight as well as the strain of stripping are placed on one side or edge of the punch. In extreme situations up to 1/2" of the punch could break off.
You can control certain aspects of the issues we've mentioned on your shop floor. It is our duty to offer you the finest punches. We accomplish this by using the best shock-resistant tool steels available and then machining them to precise tolerances, then harden and temper them using a stringent metalurgical processes.
Punches typically break and chip when used on high-tensile, high-strength plates more than 1/2" thick. Our engineers have created a number of extremely tough punches that perform well under these difficult conditions.
The importance of longevity in Punching Tools And Why It Is Vital
Quality control is crucial. Consumers will distrust brands that are inconsistent and undependable, regardless of their industry. Low quality equipment could result in a loss of credibility, lower production, less profits and a decrease in morale among employees. The best equipment will give you the highest return on investment whether your company is just beginning or already a successful one.
For shops that fabricate, punch tooling are critical to their operation. In fact the FMA describes them as "the Swiss army knife of the fabrication shop." Although there are many processes that can be improved to guarantee high-quality products, the first stage to ensure a highly productive efficient, cost-effective work environment is investing in punching equipment that last. Find a company that follows these top practices.
As a Materials Consultant
The primary rule to ensure long-lasting punch tools is to select the right material which is in line with the material that will be punched. A tool maker who is an expert in materials will assist you in choosing the best material for your tool. A2 steel, for instance is the one that punches were constructed from in the past. It's versatile, tough and has dimensional stability during heat treatment. If you're using high-strength low-alloy steel (HSLA) or any other highly advanced materials, A2 may be overmatched. Instead, you need a punch that has high compressive strength, like M2 or CPM-M4. Applications that require high load will benefit from M2 steel.
A shift in your mindset is essential to extend the lifespan of your punching tools. There is no doubt that using top-quality materials, adding coatings and improving your finishes can add cost to the initial tool construction. It is important to compare this with inferior materials. In addition to the cost of replacing parts, it's critical to consider the costs of lost productivity.